Derrick.



PATBNTED MAY 24, `1904.

A. Ei PARKER.

DERRIUK. Arrmouron rinnn 0011.3, 190s.

No MODEL.

WJTNESSES.-

NI/ENTOR mz Nonms rwsns co. worp-urna. wAsNINuToN, nA c.

Patented May 24, 1904.

UNITED STATES PATENT OFFICE.

ADELBERT E. PARKER, OF CHICAGO, ILLINOIS.

DERRICK.

SPECIFICATION forming part of Letters Patent No. 760,557, dated May 24, 1904.

Application led October 3, 1903.

To all whom t may concern:

Be it known that I, ADELBERT E. PARKER, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have linvented new and useful Improve-- ments in Derricks, of which the following is a specification.

This invention relates particularly to the re' volving base or foot upon which the mast, boom, and winding-gear of a derrick are mounted and is characterized by4 improvements with respect to the construction thereof, as will more fully appear from the following description and claims.

The various parts are assembled so that they can be readily taken apart for the purpose of transportation.

In the accompanying drawings, Figure 'l is a side elevation of the apparatus, and Fig. 2 is a top view thereof.

Referring specifically to the drawings, the post upon which the derrick revolves is indicated at 6, conveniently made of wood and stepped to receive the metal sleeve 7 which has an annular liange 8, upon which the base of the derrick rests and turns. At the top the post has a similar bearing-sleeve`9 for the upper bar of the frame of the base.

The frame of the derrick-base consists of two similar castings, each of which forms one side of the base, and these are joined on avertical median plane and held together by bolts 10. Each casting consists of upper and lower substantially horizontal bars-11 and 12, connected at the end by bars 18 and 14. The boom 15 isv pivoted at 16 and fits snugly between theA pieces 14, which act as side supports to prevent undue swaying or sidewise strain, while permitting the necessary vertical movement. The sockets for the posts are formed between the upper and lower bars, respectively, by bosses 17, each of which has a semicircular recess to form a socket in which the post is embraced. The mast is stepped in the frame beside the post on the opposite srial No. 175,661. on model.)

side to the boom and ts within asocket formed between the bosses 17 and lugs 1-8, projecting inwardly from the upper and lower side frames. It may be readily removed, as it is found unnecessary .to bolt it in place. The windinggear is mounted on the end of the frame opposite to the boom and comprises the usual drum 19, gear 20, and pinion 21, to the shaft of which a crank may be applied. The tackle 22 extends from the drum over a pulley 23, mortised in the mast near the foot thereof,

and over a pulley 24 in the end of the boom.

A guy 25 extends from the end of the boom to the top of the mast. x

The construction shown has great strength in proportion to the material used. The strain on the mast is applied directly to the post at two points a considerable distance apart, so

.there is no necessity for heavy castings. The

split construction is advantageous in manufacture, and the mast and boom may be stepped in the frame either before or after it is mounted on the posts.

What I claim as new, and desire to secure by Letters Patent, is-

1.- In a derrick, the combination with the post and mast, of a base-frame having upper and lower bars on each side, upper and lower sockets between the bars for the post and mast, and aboom and a winding-gear mounted on opposite ends of the frame. 2.- A derrick-base comprising joined side frames each having upper and lower substantially horizontal bars connected at the ends, adjacent sockets produced between the bars, for the post and mast, and mountings for the boom and winding-gear at opposite ends of the frames. A

In testimony whereof I have signed my name to this specification in the presence of 4two subscribing witnesses.

' ADELBERT E. PARKER. Witnesses:

SIGNA FEL'rsKoG, H. G. BA'rcHELoE. 

